Green batteries

In one more step of a global effort to develop greener battery technology, researchers at Rice University say they have found a way to replace a costly metallic component in lithium-ion batteries with material from a common plant.

While many of today’s lithium-ion batteries incorporate cobalt, which has to be mined and then altered at high temperature for use in batteries, Rice researchers say they can accomplish the same function using a dye extracted from a plant.

Reaching into an oxygen-free box to combine and assemble materials, researchers have shown that in altered form the plant-based substance can be incorporated into a lithium-ion battery that is almost as effective as today’s versions, said Leela Mohana Reddy, the lead researcher in the effort.

The chemically altered dye can hold and move the energy-carrying lithium ion in the same way as lithium compounds involving cobalt or other substances. The material was derived from a small flowering plant called a madder, native to southern Europe and the Mediterranean region. Scientists are testing other dyes that could prove even more effective, Reddy said. His group’s findings appeared last month in Nature’s online journal Scientific Reports.

Although the science behind the green battery component is in its early stages, if developed further it could lead to a change in one of three main battery parts: the cathode. Simply changing that component would increase the sustainability of battery production, Reddy said.

“You don’t have to do any mining,” he said. “You just plant and then you can turn it into a dye and then into a battery material with simple chemistry at room temperature.”

Batteries, especially rechargeable batteries, will be increasingly important as we move – however slowly – towards less dependence on oil. We also know that less dependence on metals that need to be recycled is a good thing as well. It’s great to see some of the leading research on this new technology be done at Rice. If we’re really lucky, some hot new startup will emerge from this research. And if nothing else, this story gave me the opportunity to post this little blast from the past: